The present invention relates to an additive containing vegetable protein hydrolyzates for cosmetic preparations.
Cosmetic preparations can be divided roughly into two types:
(a) Tenside-containing preparations having principally a cleaning action,
(b) Skin-care cosmetic preparations.
Both kinds must contain components which exercise a protective function on the skin of the user. In the case of the first type of preparation, the components are intended to mitigate or prevent the negative phenomena accompanying tensides, namely excessive soil removal, destruction of the acid environment of the skin, and the occurrence of roughness on the skin surface. In the second type of cosmetic preparation, the action of the additives is characterized by the formation of a protective film, e.g. against external influences on the skin.
For the above-named purposes, animal protein hydrolyzates, for example, are used. They have a good solubility in water, but often, even in the presence of tensides, they do not have a sufficient foam stabilizing action. It must also be considered a disadvantage that these additives are not soluble in alcohol; their application in alcohol-containing preparations is thus limited. A third deficiency is that animal protein hydrolyzates alone, without additives, do not have any kind of moisture-preserving properties.
The use of protein hydrolyzates of vegetable origin as additives for cosmetics is likewise known. They are offered to the cosmetic industry, for example, by Brooks Industries, Inc., U.S.A. (1985). They are obtained chiefly from soya. Their molecular weights run around 1000. Cosmetic products containing these ingredients, however, are lacking in foam stability, good foam formation and sudsing ability. They have no film-forming properties and hence no moisture-preserving properties, rendering them of no interest for use in preparations for skin care.
The present invention therefore addresses the problem of devising an additive for cosmetic preparations which is to contain protein hydrolyzates and which is to have a wide range of usefulness. For this purpose, it must be easily soluble in water and also in alcohols to at least 30 percent by weight. In addition, it must combine good foam formation, good foam stabilization and good sudsing ability in the presence of even small amounts of tensides. As regards its effectiveness, it is to have film-forming properties and skin moisturizing properties. The sum of these physical and physiological properties would make this additive containing vegetable hydrolyzates universally useful both in cleansing and in skin-care cosmetics.